Electric switch.



S. F. JOHNSON & L. P. AYRES.

ELECTRIC SWITCH.

APPLICATION FILED JULY 21.1914.-

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S. F. JOHNSON & L. P. AYRES.

ELECTRIC SWITCH.

APPLICATION FILED JULY 21.1914.

1 ,21 9,002. Patented Mar. 13, 1917.

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ELECTRIC SWITCH.

APPLICATION FILED JULY 27.1914.

1 ,21 9,002. Patented Mar. 13, 1917.

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SOLOMON F. JOHNSON AND LEVI P. AYBES, OF INDIANAPOLIS, INDIANA.

ELECTRIC SWITCH.

Specification of Letters Patent.

Patented Mar. 13, 1917.

Original application filed December 15, 1913, Serial No. 806,751. Divided and this application filed. July 27,

To all whom it may concern:

Be it known that we, SOLOMON F. JOHN- SON and LEVI P. AYRns, citizens of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented new and useful Improvements in Electric Switches, of which the following is a specification.

This invention relates to electric circuit closing and opening devices and more specifically to a device of the class described, in which the opening and closing of the circuit may be accomplished by very slight movement of cooperating parts and yet without sparking or other objectionable incidents and is a. division of our application Ser. No. 806,751, filed December 15th, 1913.

It is an object of this invention to close and open a circuit by making or breaking a face contact, between conducting members, extending over a substantial area.

It is another object of this invention to so move said conducting members rela tively to one another that the face contact specified will be made or broken by a movement substantially normal to the contacting surfaces, whereby there will be no sliding of one conducting surface over the other and when contact is made no spark or a very slight spark when the contact is broken.

It is another object of this invention to construct the circuit closing and opening device in such a fashion that the said de vices will tend to spring into and to maintain a firm contact, yet may be separated by a very slight movement in order to open the circuit.

Other objects and advantages of this invention will appear as the description to follow proceeds.

In the drawings:

Figure 1 is an elevation partly in section of our circuit closing and opening device shown as attached to a dynamo.

Fig. 2 is a plan view partly in section of a portion of Fig. 1.

Fig. 3 is an enlarged detail perspective View of the circuit closing and opening device.

Serial No. 853,302.

Fig. 1 is a view similar to Fig. 2 with a modification of our device.

Fig. 5 is an enlarged detail perspective View of the circuit closing and opening device shown in Fig. 1.

1 represents the casing of dynamo upon which our device is shown as applied. Firmly seated upon the casing 1 by meansof screws 2, is an insulating block 2 having a groove or slideway 3 therein and provided with a recess 4, in which is mounted. the plunger 5 forced outwardly by the compression springs 6 whose tension may be regulated by the adjusting plunger 7 through the threaded shank 8 and nut 9. The block 2 is cut away at its upper surface as shown at 10 and in the cut away portion thereof are mounted the resilient switch blades 11 each secured to the contact block by metallic screws 12 provided with binding screws 13 to form the terminals of the switch. The switch blades 11 in the modification disclosed in Figs. 1 to 8 are provided with angular extensions 14 to form seats for the screws 12 and integral inclined braces 15 bearing against the blades 11 at 16 to brace and stiffen the same and render them more resilient. .The forward ends of the blades 11 have inwardly extending angular portions 17 and outwardly flaring ends 18 forming angular projections which constrict the space between the spring blades adjacent their forward ends.

Slidably mounted upon the casing 1 of the dynamo is a sliding plate 19 to which is rigidly secured the insulating plate 20 having integral therewith the upstanding insulating block 21 of substantially cylindrical form and provided with the recess 22 to accommodate the nose of the plunger 5. Secured to the cut away face 23 of the block 21 by the screw 24 and resting upon the plate 20 is a conduct-ing plate 25 having beveled sides 26, the angle of which is precisely the same as the angles of the flaring end of the switch blades 11. The plate 19 has a downturned extension 27 through which extends the dynamo shaft 28 and through which sliding motions are imparted to the plate 19 to make and break the circuit by governor controlled moans forming no part of the in vention set forth, but fully described and claimed in our co-pending application above noted. A cap incloses the switch and is locked in position by the spring catch 30.

In operation the plate 19 is moved back and forth in the recess 3 to open and close the switch, spring plunger 5 tending to keep the switch open-by forcing the plate 19 rearwardly away from the switch blades 11. As the plate 19 moves forwardly the rounded forward surface of the block 21 will force the flaring ends 18 of the switch blade 11 apart until the angular projections formed by the portions 17 and 18 of the switch blades pass the widest part of the block 21 .whereupon these blades in the continued movement of plate 19 will come together, ultimately coming to rest in the notches 31 between the block 21 and the contact plate 26, in which position the faces of the flaring ends 18 will be in face contact with the beveled edges 26 of the conducting plate. It is to be particularly noted that this contact is made without any sliding action whatever, the flaring ends 18 being eased into contact with the beveled edges 26 in a direction substantially at right angles to the said edges. After contact is once established there is a small sliding movement of one conducting surface over the other. This is beneficial as it serves to keep the surface clean and free from carbon.

The reverse operation takes place when the plate 19 is either pulled rearwardly or forced rearwardly by the spring plunger 5 in which case the angular projections between the parts 17 and 18 of the spring blades cause the faces of the flaring ends 18 to separate at once from the beveled edges 26 in a direction substantially normal to the said beveled edges in such a way that the face contact although of considerable area, is broken by direct separation with no sliding action whatever. It is also to be particularly noted that the slightest movement of the plate 19 serves to completely disengage the contacting members by moving one pair thereof directly away from the other pair without sliding action and it is further to be noted that the inward angular projections on the spring blades automatically tend to set themselves in the notches 31 and thus to maintain a firm con tact while the switch is closed.

In Figs. 4 and 5, we have disclosed a modification of our device. In this modification we provide upstanding insulating blocks 35 secured to the dynamo casing by screws 36 and connected by the tie-piece 37.

'To the insulated blocks 35 are secured the switch blades 38 by means of angle pieces 39 and screws 40 upon which are mounted the binding screws 41 to form the terminals of the switch. The forward ends of the spring blades 38 in this instance are provided with inwardly extended angular portions 42 and outwardly flaring ends 43, the angle extensions 42 being long enough to materially constrict the passage between the spring blades. In this construction the spring blades are shorter and no pressing means is used to brace them. Slidably mounted upon the dynamo casing by means of a slot 44 and a thumb screw 45 in an obvious manner is a sliding plate 46 having mounted therein by means of screws 47, the insulating block 48 upon which is a boss 49. Integral with the boss 49 and rising upward therefrom is a polygonal insulating member 50 having beveled sides 51 and 52. Secured to the rear of the insulating block 50 by the screw 53 and resting upon the boss 49 is the conducting block 53 having beveled sides 54. The blade 46 has a down-turned rear extension 55 which is governor controlled to advance and retract it by mechanism forming no part of the invention herein disclosed but fully described and claimed in our co-pending application above noted. Upon the member 37 is mounted a coiled spring 56, the forward end of which abuts against the face of the insulating block 50 and tends to force the latter rearwardly to open the switch.

The operation of this modification is substantially the same as that of the other. If the block 50 is moved forwardly the flaring ends 43 of the spring blades first move outwardly and then come together into the notches 57 in such a fashion as to bring them into direct positive face contact with the beveled sides 54 of the conducting block 53, the resiliency of the blades tending to hold them in firm contact unless the circuit is positively broken and when so broken a very slight movement of the plate 46 will separate the contacting elements without sliding motion and without material sparking.

We have shown our new switch as applied to a dynamo or generator and the supports and coiinections are therefore those particularly adapted to such use of the switch and susceptible of being readily controlled by a governing device, such as described and claimed. in our co-pending application. It is of course, however, to be understood that the particular supports and connections illustrated in connection with the switch may be modified and changed without departing from the scope of the invention.

We claim A. circuit closing or breaking device com prising a pair of spring blades having a constricted throat portion but outwardly angularly bent ends, a contact member comprising an insulating block having a rounded front face and having its rear face beveled on both sides to accommodate the our names to this specification in the pres- (onstricteg pfrtion of thie blalclles, 231d a c10nence of tWo Witnesses.

ucting 0c associate Wit sai insu ating block and having contact faces parallel g g g g fi 5 with the ends of the blades, said combined blocks forming V-shaped notches having fiat Witnesses: faces, substantially as described. LEWIS J. BURNETT,

In Witness whereof, We hereunto subscribe ELLIOTT AYRES.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

